


Both Sides of Time

by theoretically_moss



Category: Fire Emblem Series, Fire Emblem: Fuukasetsugetsu | Fire Emblem: Three Houses
Genre: Angst, Azure Moon Route, Crimson Flower Route, F/F, Fire Emblem: Three Houses Black Eagles Route Spoilers, Fire Emblem: Three Houses Blue Lions Route Spoilers, M/M, Post Timeskip, twin byleths au
Language: English
Status: Completed
Published: 2019-09-17
Updated: 2019-09-18
Packaged: 2020-10-20 13:13:55
Rating: Teen And Up Audiences
Warnings: Graphic Depictions Of Violence, Major Character Death
Chapters: 2
Words: 1,877
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/20675957
Author URL: https://archiveofourown.org/users/theoretically_moss/pseuds/theoretically_moss
Summary: Fodlan was ravaged by war and two siblings stood at the center of it all, pointing their blades at each other. One must die at the cost of another's love and ideals, such were the ways of war.





	1. Stand by Her Side

**Author's Note:**

> I keep on seeing artwork and ideas about twin Byleths in which m!Byleth sides with Dimitri and f!Byleth sides with Edelgard and I'm also fueled by art of Hegemon Edeleth, so I needed to write this fic. I had a burning passion for a twin AU fic in which Edelgard and Byleth are losing. If no one else would write this, I would and then I'd cry.
> 
> Byleth = f!Byleth  
Bilet = m!Byleth

**Summary for the Chapter:**

> The war was coming to an end, but at what cost. Byleth stood her ground alongside Edelgard, protecting her to the very end, even against her brother, Bilet, and King Dimitri.

Edelgard stood, stalwart as ever as she spoke with an imperial general. “The time has nearly come”

The woman nodded in response. She had finished the procedure the Emperor requested, putting the instruments aside. “Yes, the anomaly should present itself shortly. However...” She trailed off, knowing full well what would occur.

The Emperor shook her head, a wry smile on her face. “There’s no reason to fret. Besides, it’s far too late to second guess. Now, assume your position. I can’t promise your safety if you remain here.”

The general bowed, turning and taking her leave. Edelgard quickly turned her attention to her ever-present tactician and commander. “Byleth, that means you, too.”

Byleth only stepped closer to her Emperor, slipping her hand into Edelgard’s. The red-gloved hand was adorned with a small silver band, one Byleth had given her not too long ago. She knew that they would either win or die in this battle. No matter the result, she wished to live without regrets, knowing her feelings were out there and shared. “I promised to walk this path alongside you, didn’t I? I won’t leave your side now.”

Edelgard returned a sad smile, placing her free hand on Byleth’s cheek. “My love…” Her words came to a halt as she let out a pained shout, pulling away from the former professor. Her flesh convulsed as monstrous clumps began to warp out of her body, reforming it. Noticing her love’s look of concern, she spoke. “This pain is nothing...compared to what I have already suffered…”

Her breathing became heavy as more pained groans came from her, until her flesh settled into the disgusting form of a monster. Byleth kept her focus on Edelgard’s face though, stepping towards the Emperor and placing a hand on her cheek. It was still Edelgard’s human cheek as the monster leaned down into the touch. Byleth stood on her toes, a single tear falling down her face as she pressed a kiss to the monster’s lips. Their faces remained close as she whispered. “We’re in this together, El. To the very end. No matter where that may be.”

* * *

She was weak, but Bilet wouldn’t kill her. He was always so weak and sentimental, having difficulty finishing off the enemies he fought. Though maybe that wasn’t the case anymore. Byleth stared at the dead bodies littering the throne room. So many good people she had worked alongside, felled by the hand of her own brother. She returned her gaze back to Bilet, his hand was outstretched to her as she knelt upon the floor. Just like Dimitri had done for Edelgard. The look on Bilet’s face was a sad one, filled with concern. “Is this what you wanted?”

There were many things she wanted, but this situation? This was not one of them. She wished her brother wasn’t blinded by his love for Dimitri. That he would see the sense in Edelgard’s world and join her in taking down the church. Yet here they were. Byleth couldn’t help but stare lovingly at Edelgard’s limp body. “No.” She started weakly between breaths. Slowly, she raised her half of the Sword of the Creator. “However, I don’t regret choosing this path.” She plunged the blade in her stomach, pain searing through her body as she tore her insides apart. “Goodbye, brother. I have a...pro…mise...”

She fell with a loud thud, her vision darkening as she stared at Edelgard’s still face. A weak smile crossed her lips as she placed her hand in her Emperor’s. This was the end and she promised to be with her every step of the way, including the afterlife. The last sensation she felt as the darkness enveloped her were drops of water that landed on her face. But even that sensation faded as the darkness turned to a light, leading her into a field of flowers as she stared at Edelgard’s beauty. The Emperor turned, a sad smile crossing her face as she saw Byleth. The two ran to each other, pulling into a warm embrace. “I’m here with you, to the end and beyond, El.”

* * *

Bilet stood over his sister’s corpse, her blood pooling around his feet. How could she do this to him? Leave him behind with her blood staining him. Tears fell, landing on her peaceful smile and mixing into her blood. His open hand fell to his side as he raised his head to the sky. If only she could see the pain this war brought. If only they could have stood together to protect the people. Would Jeralt be disappointed in them? Fighting to the death like this? The only response Bilet got was a warm hand entering his own.

Dimitri was there for him. He always would be. They promised to protect each other and see the world into an age of peace. Byleth seemed to have made a promise of her own. Bilet closed his eyes as more tears streamed down his face, his body wracked with silent sobs. A memory of the two of them, still children as Byleth held him close, comforting him from the terrors of the previous battle. _ “Nothing will separate us. I promise.” _

“You kept a promise to her, but you forgot about ours.”


	2. Never Leave Him Again

**Summary for the Chapter:**

> The war comes closer to it's end as Byleth and Edelgard make their advance on the Holy Kingdom. Dimtri and Bilet must make their last stand against the conquerors, but war comes at a cost.

**Notes for the Chapter:**

> I needed to write the reverse situation. I needed this. I love twin Byleth AUs when they're gay and are sadly put against each other.

Bilet stared up to Byleth. She held her sword at her side, unwilling to point it at her defeated brother. Just behind her stood Edelgard, hoisting her axe up to execute Dimitri. Bilet’s eyes widened as he watched the axe come down, severing the King’s head from his body. Byleth closed her eyes and turned her head away as a scream escaped Bilet’s lips. He watched in agony as his love’s body slumped to the ground, blood pooling and mixing with the rain, causing the ground of the stoney ruins to run red. His eyes flitted over to Byleth, who still looked away, filling his heart with a rage. “You can’t look away from what you’ve done! You chose this path, so you must suffer the consequences!”

The pain in Byleth’s face worsened, still unwilling to face what she’d brought about. She had always been the more fierce of the two, the more willing to bring an end to life, so why did he hesitate now? Why was she unwilling to look at the death she brought about here? It made the embers of rage burn bright in Bilet’s heart, forcing him onto his feet as he drew his sword. He rushed at her, prepared to kill his sister for what she had done. Yet his blade never met flesh. There was a distinct clang with metal as the sword flew out of his weak grip. Edelgard had rushed forward, protecting Byleth with her shield.

Breathing heavily, Bilet stared at his sister, her gaze now directed at him with a glare. That same glare she would always wear when she lectured him as a child. He knew they were twins, but she always acted like an older sibling, protecting and lecturing him when need be. But this time she would not protect him and this was no lecture, but a battlefield. A battlefield where they stood on opposing sides. Bilet lowered his gaze back to Dimitri’s body. His blue cape now soaked with blood. The white fur that adorned his neck now stained red. Firm hands gripped Bilet’s collar, forcing him to look up at Byleth’s face. One could almost confuse her look for one of anger, but Bilet knew better. Her face spoke of disappointment and sadness. Both for him. “Are you truly okay ending things like this?! One feeble attack and then you give up?!” Her voice lowered, almost to a whisper. “Bilet, please, let us stand together.”

Bilet stared at her, eyes wide. Had she remem bered their promise? A promise to stay together. Yet, he remembered another promise as his eyes fell once again upon the King. He brought his hands up, resting them upon his sister’s. “I’m sorry, but there’s only one way to end this.”

Byleth’s grip on his collar slackened as her eyes filled with fear. Bilet couldn’t stand to look at those eyes as he continued. “I need to break our promise and fulfill another. Please, I can’t leave him. Not again.”

He fell to the ground, Byleth’s grip releasing as he bowed down, begging. Seeing Dimitri’s blood flow on the ground beneath him strengthened the resolve of his final words, and yet they still came out as a broken plea. “You must kill me. Please.”

The sound of Byleth’s armor rung in his ears. He saw her feet move, preparing to bring down her blade, to strike down her lost brother. A wry smile came across his face as he looked up at her one final time. He had one last thing to tell her as she prepared to bring down her blade. “I’ll say hi to dad for you. Don’t forget, I still love you, By--”

His words were cut short as Byleth’s blade came down with a shout. The world turned dark, leaving Bilet all alone. He opened his eyes to find a light and Dimitri’s face. The King was crying. For him. “Why would you--”

Bilet held Dimitri’s face in his hands, placing his forehead on the King’s. “I swore never to leave you again. That includes now.”

* * *

“I still love you, By--”

In a panic, Byleth brought her blade down on her brother. Her blade silenced him. She shouted in pain as she killed him. Bilet’s blood was now on her hands and she would never be able to wash that away. And yet he never stopped caring for her, despite everything. Her hands trembled at the thought of what she had done, dropping her half of the Sword of the Creator. She fell to her knees, picking up her brother’s corpse and hugging it close. Her body wracked with sobs as her tears mixed with blood and rain. Her voice came out as a broken whisper. “If only there was another way. Then this wouldn’t have to happen.”

She felt a hand rest atop her head, providing a reassuring pat. It was Edelgard, Byleth had no doubt about that. But for now, she could only focus on her dead brother. There were so many things she wished to curse for bringing this about. Damn the crests. Damn the church. Damn Rhea. And damn promises. A small part of her was angry at Bilet. Angry he made a promise to Dimitri that would conflict with their own. How dare he abandon his own sister like this. All those lectures, all that time she spent protecting him, all of it amounted to nothing. She wanted to protect one of the people dearest to her. One of the people who made life worth living. And here he was. Dead by her hand.

Eventually, the rain and her tears stopped. She carefully placed her brother’s body next to Dimitri’s. She had no doubt that’s what he would have wanted. Standing, she faced Edelgard, the Emperor’s face filled with concern, asking a wordless question. Byleth simply shook her head, looking off into the distance. “I’ll be fine. I just hope we can give them a proper burial when this is all over.”


End file.
